<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <div id="app">
    <button @click="add">加1</button> 
    <div ref="test">{{ count }}</div>
  </div>
</body>
<script src="lib/vue.js"></script>
<script>
  new Vue({
    el: '#app',
    data: {
      count: 100
    },
    methods: {
      add () {
        this.count++
        this.$nextTick(function () {
          console.log(this.$refs.test.innerHTML)
        });
      }
    },
  })
</script>
</html>